60Coγ射线对高免卵黄液中EDS-76病毒灭活的研究

用不同剂量、剂量率的^60Coγ射线对卵黄液中的EDS-76病毒进行辐照,研究了其对病毒的灭活效果和对卵黄抗体(IgY)的影响。结果表明,^60Coγ射线辐照,可以灭活高免卵黄液中的EDS-76病毒,且随辐照剂量、剂量率的增大,灭活率也增高;EDS-76病毒在卵黄液中的D10值为0．57kGy～0．60kGy;6．0kGy的辐照剂量,可以将高免卵黄液中的EDS-76病毒完全灭活,且不影响卵黄抗体效价,该卵黄抗体稳定性好、耐酸、耐热、耐蛋白酶消化。     

泡椒凤爪微生物污染来源及辐照杀菌效果的研究

研究了泡椒凤爪生产流程中微生物污染来源、60Co-γ射线辐照杀菌效果、及不同剂量处理的产品在不同温度下微生物繁殖情况。结果表明:泡椒凤爪微生物污染主要途径是泡制和包装环节,这是产品卫生质量控制的关键控制点;60Co-γ射线对产品中微生物有很好的杀灭作用,能显著延长产品的保质期,辐照剂量为6 kGy时,产品在30℃、20℃、10℃温度条件下保藏,保质期比对照分别延长了53 d、120 d和180 d。     

60Coγ射线对高免卵黄液中霉形体杀灭作用的研究

用^60Coγ射线处理高免卵黄液,研究了不同剂量、剂量率对霉形体的灭活效果和对卵黄抗体的影响。结果表明,^60Coγ射线可以完全杀灭高免卵黄液中的霉形体,霉形体在卵黄液中的灭活剂量为6．0kGy;10．0kGy以下的辐照剂量不影响卵黄液中蛋白质含量、pH值和活性氧自由基,同时不影响抗体效价。     

辐照保藏豆制品的研究

豆制品用聚乙烯复合袋分装后,经4kGy、6kGy、8kGy、10kGy的^60Co γ-射线辐照,分别在5℃、25℃条件下贮藏,定期对其进行微生物、感官及营养成分指标检测。经检测分析,豆制品在一定剂量范围内辐照,效果良好,无异味,降低了微生物数量,对营养品质无不良影响,延长了货架期。研究结果表明,用6kGy～8kGy的剂量的γ射线辐照保藏豆制品效果最佳。     

钴—60对高兔卵黄液中大肠杆菌的灭菌研究

用钴－60γ射线对接种于卵黄液中的大肠杆菌进行辐照灭菌,并测定了卵黄液的抗体效价、活性氧和卵黄液保存期的变化。结果表明：1.大肠杆菌在卵黄液中的D10值为0.31-0.37kGy,杀灭卵黄液中大肠杆菌的照射剂量为3kGy;2.辐照量在15kGy以下时,对卵黄液的抗体效价没有影响或仅有轻微影响;3.经8kGy照射后的卵黄液在常温、4℃、-10℃条件保存时,保存期明显长于未照射的卵黄液。     

用红外光谱法研究60CO-γ射线辐照对三斑海马粉主要成分的影响

为了考察辐照剂量对名贵中药成分的影响,本研究用红外光谱法对经剂量为0、1. 5、3、4. 5、6、9、12、15、18、19. 5和21 kGy辐照的三斑海马粉进行了研究。蛋白质是三斑海马粉的主要成分,其含量高达70%以上。结果表明,经1. 5、3、4. 5和6 kGy剂量辐照,样品的红外光谱中代表蛋白质与脂类吸收带的峰形与峰位几乎没有变化,而高于9 kGy的剂量辐照后,样品的红外光谱代表蛋白质与脂类吸收带的峰形与峰位变化较大。由此可说明,辐照剂量不超过9 kGy,辐照对样品的蛋白质二级结构影响较小;剂量高于9 kGy辐照后,辐照对样品的蛋白质二级结构影响较大。此研究结果可为核辐照企业对三斑海马粉辐照剂量的设置提供参考。     

蛋黄液辐照杀菌技术研究

通过测定液蛋黄的酸价、过氧化值和TBA值,研究辐照剂量对蛋黄液氧化和杀菌效果的影响.结果表明,蛋黄液经辐照后,蛋黄液中脂肪氧化程度随着剂量增大而增加.0.4 kGy能够完全杀灭微生物,且感官指标不发生变化.     

红油金针菇产品的辐照加工技术研究

研究了红油金针菇的辐照加工技术,通过正交试验确定了红油金针菇的最佳调味配方,结果表明：红油添加量10%、蔗糖添加量0.1%、食盐添加量3%、柠檬酸添加量0.2%为最佳调味配方。研究红油金针菇的防腐杀菌技术的结果表明：添加0.015%的脱氢乙酸钠和0.015%的山梨酸钾复配防腐剂比单一防腐剂更有效提高了红油金针菇的防腐效果,辐照剂量为4kGy杀菌后的红油金针菇可达到完全灭菌的效果。将上述杀菌处理后的红油金针菇进行常温贮藏,180d后红油金针菇产品细菌总数仍然很少并且保持有令人满意的色泽、脆度和口感。辐照处理对红油金针菇的营养成分影响不大。     

60Co-γ射线辐照人体胎盘羊膜保鲜研究及应用

新鲜人体胎盘羊膜是一种新型的生物敷料.具有来源广泛、成本低,贮存使用方便,对烧伤创面有良好的保护作用,促进创面及早封闭、愈合等优点.本文对离体8小时之内的鲜人体胎盘羊膜辐照灭菌、保鲜方法及临床应用进行了研究.供试样品经清洗、灭菌、脱脂、脱水等预处理后,制备成15×10cm2的羊膜,分装于尼龙-聚乙烯复合袋中,抽真空封闭包装待辐照.辐照处理由黑龙江省农科院原子能利用研究所具有微机自动控制及旋转辐照台的60Co-γ射线辐照10-14kGy后,微生物检测仍为阳性,达到16kGy吸收剂量以上时,微生物检测为阴性.常温(平均15℃)条件下贮存180天,0-14kGy处理组微生物检测阳性,并发生不同程度的胀袋、变色.16-24kGy处理组虽然微生物检测为阴性,但颜色发生褐变并出现异味而失去应用价值.低温(平均5℃)避光条件下贮存180天,16-24kGy处理组微生物检测为阴性,颜色、气味与新鲜对照样品无显著性差异.经哈尔滨医科大学临床应用16例病人,26个烧伤创面的覆盖试验,保鲜的人体胎盘羊膜止痛率100%,创面渗出明显减少,防止了创面的枯干及病原微生物的二次污染,使"间生态组织"迅速恢复生机而避免发生坏死,创面愈合后表面光滑,无明显瘢痕增生.     

60Co γ辐照对普洱茶杀菌效果及其品质的影响

以普洱茶为研究对象,利用60Co γ射线辐照,初步研究了不同辐照剂量对普洱茶的杀菌效果及其品质的影响。结果表明:60Co γ射线能有效地杀灭普洱茶中的微生物,产品初始细菌和霉菌的数量均低于105cfu/g,经3.6kGy~5kGy剂量辐照能确保普洱茶中污染微生物的量低于1×103cfu/g,而且对普洱茶主要品质成份无明显影响。     

A note on piglets’ preferences for drinker types at two weaning ages

Piglets weaned younger than 3 weeks of age often exhibit excessive amounts of drinking behaviour compared to pigs weaned at later ages. Piglets of different ages may be attracted to different drinking devices because of the oral motor patterns used for drinking from them or because they provide different amounts of tactile stimulation to the snout. Therefore, this study was designed to examine individual piglet preference for drinker type when piglets were weaned at two different ages. In three separate experiments, newly weaned piglets’ preferences for drinker devices were examined through 10 days after weaning. In all three experiments, individually housed piglets were weaned at either 19 or 26 days of age and given access to two drinker devices (either a nipple drinker and a push-lever bowl drinker or a push-lever bowl drinker and a float bowl drinker). According to both drinking behaviour and water intake, pigs preferred the nipple drinker or the float bowl drinker rather than the push-lever bowl drinker. These results suggest that piglets prefer a drinker that is easy to find or simply provides easier access to water.     

白色基因座(I)在中国地方猪种毛色遗传中的作用研究

通过利用PCR—RFLP和PCR—SSCP技术对中国地方猪种KIT基因内含子17、18的序列进行多态性分析。结果表明：内含子17上的替换突变(G→A)发生于毛色为白色的个体——白色五指山猪、大白猪、长白猪上,其基因型(AB型)频率分别为1、1和0．8;其他中国地方猪种的此基因型频率均为0。内含子18上的缺失突变(AGTT)也同样发生在上述3个猪种的白色个体中,其基因型(AA型)频率分别为1、1和0．93;而且同样在其他的地方品种中其基因型频率均为0。这充分证明KIT基因对于猪的白毛色有重要的调控作用,而且I基因座对于其他的经典遗传基因座有上位作用。另一方面,中国地方猪种荣昌猪虽然在表型上与引入猪种大白猪、长白猪相似(白毛色),但是在KIT基因上发生的突变完全不同,推测它们分别属于不同的毛色遗传体系。     

微波处理对绿竹笋保鲜的影响

对微波处理后绿竹笋的酸性洗涤纤维(acid detergent fiber, ADF)质量分数的变化及保鲜情况进行了研究,结果表明:ADF质量分数的增加,前期快、后期慢;对照(微波0 s)ADF质量分数增加速率显著高于各微波笋样;微波对其抑制作用明显.笋保鲜时间受到微波、微生物等因素的影响;低温保存、无保鲜剂涂膜,竹笋到第8天仍具较好的可食品质.     

Permeabilization of cell membrane by programmed form of electrical pulses

The role of the shape of electric pulses of cell permeabilization and lysis was studied using the newly developed DPS electroporator. The effects of bipolar pulses, steep rising and falling edges in the pulses, delays between pulses, and shapes of DC signals between the edges on the lysis of bovine oocytes and the permeabilization of their cell membranes were investigated. Comparing the permeabilization rates with the lysis rates revealed a number of correlations, which make it possible to optimize the pulse shapes for achieving maximum permeabilization rates while keeping the lysis rates low. The optimization of pulse shape is essential for improving the procedure of electroporation in mammalian cloning technology.     

Single nucleotide polymorphism analysis on melanocortin receptor 1 (MC1R) of Chinese native pig

Thecoatcolorisanimportantcharacteristicofapigbreed,andcanbeclassifiedintomanytypes.Thecolorvariationsareeitherduetothedistributionofmelanocytesintheskinortotheabilityofmelano-cytestoproducemelaningranules.Thesynthesisofmelaninoriginatedfromtheformationofneuralcrest-derivedcells,whichhavetwomigrationroutes[1,2].Themelanocytesaretheramificationswhiletheneuralcrest-derivedcellsmigrateviadorsalroute[3].Andtheyprovidethefactoryformelaninsynthesis.Al-thoughtherearemanykindsofpigmentsinvertebralanim…     

The influence of taste stimuli and illumination on electrogastrogram measurements

An electrogastrogram (EGG) is considered to be an index to the autonomic nervous system of the digestive organs. In the present study, we attempted to clarify whether or not an EGG can be used to evaluate the influence of illumination, and what kinds of effect taste stimuli and illumination have on the autonomic nervous system. In this study, we used the ratio of the normal wave component of the EGG (EGG-NR: 2-4.5 cpm power/1-10 cpm power) and the amplitude of a normal wave (EGG-NI: integrated EGG of 2-4.5 cpm). Thirteen healthy males participated in 16 experimental conditions (4 lighting conditionsx4 taste stimuli). The four lighting conditions were set by combinations of illuminance levels of 200 and 1500 lx and color temperatures of 3000 and 7500 K. The four taste stimuli were sweet (glucose), salty (salt), sour (acetic acid), and bitter (quinine). The changes in EGG-NR and EGG-NI were compared for different taste conditions. The results showed that EGG-NI was not significantly affected by the different taste conditions. However, the main effect of taste on EGG-NR was significant: sweet and salty tastes were significantly higher than the bitter taste. EGG-NR and EGG-NI in different lighting conditions were also compared. The main effect of different color temperatures was also significant, but the illuminance level did not affect EGG-NR. EGG-NR increased significantly at the lower color temperature. On the other hand, EGG-NI significantly increased at the lower illuminance. These results suggest that parasympathetic nervous activity has a predominant effect on gastric activity in different lighting environments. Therefore, EGG measurements may be useful indicators for illumination environment studies.     

Adenylate cyclase responses to sucrose stimulation in membranes of pig circumvallate taste papillae.

1. Typical adenylate cyclase (AC) responses to guanine nucleotides were found in membranes of pig circumvallate (CV) taste papillae. 2. Sucrose stimulated AC activity in the CV membranes and this stimulation was GTP dependent and tissue specific. 3. The stimulatory effect of sucrose in the CV membranes was dependent on the concentration of membranes used in the AC assay. 4. This study provides the first biochemical data on cellular transduction of taste in the pig, compares positively to preliminary results in cattle and supports recent suggestions for a role of cAMP in sweet taste transduction.     

Effects of color temperature of illumination on physiological functions

This article presents our recent studies on the effects of color temperature on the taste sense and the influence of color temperature on bright light exposure during night rest period. Ten male Japanese and ten male Chinese were exposed to four illumination conditions (200, 1500 lx x 3000, 7500 K). Their taste threshold of four common tastes and amount of saliva were measured. It was found in both Japanese and Chinese subjects that sensitivities to sweet and bitter taste were decreased under the lower illuminance condition. Under the lower color temperature condition, sensitivity to bitter taste in Japanese and sweet taste in Chinese were decreased. Secretion of saliva increased under the lower illuminance condition in both Japanese and Chinese. Only in Chinese subjects, secretion of saliva increased under the lower color temperature condition. In a separate experiment, six male Japanese students were subjected to bright light exposure during a night rest period. They performed a mental task from 23:00 h till 02:00 h, and took a rest from 00:00 h to 01:00 h. During the rest period they were exposed to bright light (3000 lx) of three different color temperatures: 3000 K, 5000 K, and 7000 K. After exposure to bright light of 3000 K but not at other color temperatures, the EEG alpha1 band ratio and the beta band ratio at 02:00 h were higher and lower, respectively, than that at 01:00 h. These findings indicated that lower color temperature bright light exposure during a night rest break led to a reduction of subjects' arousal level during the subsequent work. Herein, we discuss these results from the viewpoint of physiological anthropology.     

Single nucleotide polymorphism analysis on melanocortin receptor 1 (<Emphasis Type="Italic">MC1R</Emphasis>) of Chinese native pig

Melanocortin receptor 1 (MC1R) gene, one of the important candidate genes for coat color trait, was used to analyze the single nucleotide polymorphism (SNP) in Chinese native pig breeds by PCR-single strand conformation polymorphism (PCR-SSCP). The study had also taken 3 imported pig breeds as control. The results showed that the three mutations G284A, T309C and T364C found in Chinese native pigs were consistent to the mutation found in the European Large Black individuals. However, 68CC or C492T and G728A were only found in the imported individuals, which were obviously different from the Chinese native pigs. Accordingly, we presumed that the coat colors of Chinese native pigs belonged to dominant black color system, which was completely distinct to that of imported pig breeds. Thus it was implied thatMC1R gene was not the principal factor affecting the coat color differences of Chinese native pig breeds, but could be used to trace the molecular evolution of pig breeds.     

硫酸铜浓度和造伤对叶材保色效果的影响

本实验以15种植物的叶为试材,分别用0%、1.02%、5.85%、10.22%、14.21%和17.15%浓度90℃硫酸铜(CuSO₄·5H₂O)溶液进行保色处理,对其中不易进行保色处理的叶材人为造伤,研究硫酸铜浓度和造伤对叶材保色效果的影响。结果表明,不同叶材对硫酸铜溶液的反应不同:纸质叶材如酢浆草在热的硫酸铜溶液中易皱缩变形,革质叶材如荷兰铁和铁树,用硫酸铜热处理无效;新叶较成熟叶易于保色。硫酸铜浓度对保色效果没有影响,但对保色时间有影响,硫酸铜浓度越高,复绿时间越短,14.21%和17.15%两种浓度的复绿时间相同。保色处理的叶材干燥前后颜色有深浅变化。少数叶材如贴梗海棠不经保色处理自然干燥就能较好保持原有色彩。造伤有利于部分革质叶材的保色。